Internal-combustion engine



lillllli l- IIIL Feb 17, 1931- R. A. WEINHARDT INTERNAL COMBUSTION ENGINE Filed June 3, 1926 F/r'g Vg' Y s wfg n) @Hotmail Patented Feb. 17, 1931 UNITED 'STATESv PATENT OFFICE ROBERT A. WEINHARDT, OF DETROIT, MICHIGAN, ASSIGNOR T0 PACKARD MOTOR CAB COMPANY, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN mTERNAL-COMBUSTION ENGINE Application filed `Tune 3, 1926. Serial No. 113,494.

This invention relates to cooling systems for internal combustion engines, and more particularly to cooling systems of the evaporative type.

These systems, as is well known in the art, operate in general by the evaporation of a cooling medium from the cooling jacket, the vapors being normally led into and condensed in a radiator or condenser and being returned to the cooling jacket in any suitable way.

The rate of evaporation being dependent on the temperature of the engine, which undergoes considerable Variation according to the speed, atmospheric temperature, etc., the amount of condensate likewise varies within fairly wide limits. The pumping means employed for returning the cooling medium to the jacket, however, must be of suflicient capacity to afford proper cooling at maximum operating temperatures, with the result that when the engine is at a low temperature, the pump is to a large extent idling, and pumps at full capacity only in exceptional cases and for comparatively short intervals.

Moreover, it has been found that when antifreeze solutions are employed as cooling medium, particularly the usual solution of water and alcohol, fractional distillation takes place and results in the transfer of most of the alcohol to the condenser, leaving water free from alcohol in the cooling jacket. Then when the engine is allowed to stand in the cold, the water in the cooling jacket is much more apt to freeze and may cause serious damage. Furthermore, when the engine is started up cold, the large body of water in the cooling jacket requires considerable time to warm up, thus allowing the condensation of fuel on the cold cylinder walls which passes by the pistons and results in oil dilution.

One of the objects of this invention is to provide a cooling system which will obviate these disadvantages and will increase eiliciency and economy of operation.

Another object is to provide a cooling system wherein the pumping means shall be operated only to a suiicient degree to assure proper cooling and waste operation avoided. A further object is to provide novel means 1n a system of this kind for insuring the proper mixture of the water and the antifreeze liquid when the temperature falls below a predetermined degree, in order to prevent freezing of the water which may have been separated from the cooling liquid during the operation of the system.

A still further object is to provide novel means whereby the engine shall warm up rapidly when started cold.

Other objects .will appear hereinafter.

One embodiment of the inventive idea is illustrated in the accompanying drawings, but it is to be expressly understood that these drawings are for purposes of illustration only, and are not to be construed as a definition of the limits of the invention, reference being had to the appended claims for this purpose.

In the drawings- Fig. l shows diagrammatically one embodiment of the invention;

Fig. 2 is a diagrammatic detail showing of the pump control means; and

Fig. 3 is a detail of the thermostatic control valve.

Referring to the drawings, wherein like reference numerals indicate like parts, 1 indicates the 4cylinder block of any internal combustion engine, having a cooling jacket 2 of any suitable type. The jacket 2 is connected, as by means of a discharge pipe 3, with a suitable condenser 4 which preferably includes a condensate tank 5, a series of upright condensing tubes 6, and an air vent 7 The pipe 3 is preferably provided with an inverted U-shaped portion 8 which extends above the highest point of the cooling jacket 2 to insure that the latter is completly filled, the level of the cooling medium being indicated at 9. The products of evaporation, resultinff from the heating of the cooling liquid in jacket 2, pass through the pipe 3 to condenser 4 and gradually rise in the tubes 6 until they are condensed, the condensate collecting in tank 5. Suitable means are provided or returning the condensate to the jacket Which, as here shown, comprise a return pipe 10, a pump 11, air chamber 12, and pipe 13 which preferably discharges into pipe 3 at a point adjacent the jacket 2. A check valve 14 prevents any reverse circulation in the pipe 13.

Said ump may be of any suitable type and pre erably is of a type well known to the art which comprises an oscillatory diaphragm actuated by the plunger of a solenoid 15 (F ig. 2), which is connected in circuit with the ignition switch 16 and battery 17 of the engine.

To the end that the pump shall be operated only when there is a suflicient amount of condensate in the condenser to justify such operation, means are provided for setting the pump in operation at a predetermined level of the condensate and for stopping the pump when the condensate falls below said level. With this object in View a switch mechanism, preferably comprising a stationary contact 18 and a spring contact 19, is provided in the pump circuit, said spring contact 19 being under the control of a ioat 20 in a chamber 21 connected to the pipe 10, said ioat being provided with a plunger 22 positioned to engage and close the switch member 19 when a predetermined level of the condensate in the chamber 21 is reached.

Suitable means are likewise provided for insuring a proper mixture of the water and anti-freezing liquid, as alcohol, in the system when the engine is stopped and the temperature falls below a predetermined degree. This is accomplished Aby extending a drain pipe 23 from said jacket at a point adjacent its lower portion, to the ipe 10 at a point adjacent the pump 11. laid drain pipe 23 is thermostatically controlled by means of a thermostat 24 of a well known type which is mounted in a suitable chamber 25 connected in the pipe 23 and is adapted toy hold a needle valve 26 closed until the temperature Vfalls to the predetermined degree when it acts to open said valve, and permit water from the jacket 2 to pass to the part of the system containing the condensed alcohol.

The operation of the system will now be readily apparent. When the engine is cold, the thermostatic valve 26 is open, and the jacket 2 is drained into the condenser 4. When the ignition switch 16 is closed and the engine started, the pump 11 immediately begins to operate, but the thermostatic valve remains open so that the cooling medium discharged into the jacket through the pipe 13 in'nnediately drains out through the pipe 23. The engine therefore warms up very rapidly, and at the saine time gradually warms the cooling medium until the thermostatic valve 26 closes. The jacket 2 then lills up with cooling medium until the level S) is reached, and the level in the condenser 4 is lowered suiiiciently toopen the switch 19 and stop the pump. The products of evaporation from the cooling jacket 2 will now be condensed in the condenser 4, until a suilicient amount of condensate collects therein to close the switch 19 and to again operate the pump.

It will be noted that during the normal operation of the engine the pump 11 will o erate just enough to keep the level of tlie cooling medium in the condenser at a predetermined point, and that all idle operation of said pump is therefore avoided. Furthermore, the cooling medium which is discharged through the pipe 13 into the pipe 3 meets the products of evaporation from the cooling jacket 2 and partially condenses them, thus further decreasing the work of the pump. In cold weather, it has been found that the pump is practically ioie duringnormal operation. When the engine is stopped in cold weather the water in the jacket 2 gradually cools until it reaches a temperature sufficiently low to cause the thermostat 24 to open the valve 26. The water from the jacket 2 is thus free to mix with the alcohol in the condenser, thereby insuring against freezing throughout the system.

While only one embodiment of the invention is illustrated in the accompanying drawings, it is to be expressly understood that the invention is not limited thereto but is susceptible of a variety o expressions, and that changes may be made in the details and arrangement of parts without departing from the spirit of the invention, and reference is therefore to be had to the appended claims for a definition of the limits of the invention.

What is claimed is 1. A cooling system for internal combustion engines comprising a cooling jacket, a condenser, a pump for feeding cooling medium from said condenser to said jacket, electric actuating means for said pump including a source of power, the ignition switch of said engine being in circuit with said means, a second switch in said circuit, float means actuating said second'switch in accordance with the level of cooling medium in said condenser, whereby said pump is intermittently operated, and thermostatic means for draining said jacket when the temperature of the cooling medium is below a predetermined degree.

2. In an internal combustion engine, a cooling system having a cooling jacket, a

condenser, a discharge conduit connecting said cooling jacket with said condenser, pump means connected to said condenser, and means connecting said pump means with said discharge conduit at a point adjacent said cooling jacket for returning cooling medium to said cooling jacket, whereby the products of evaporation from said jacket are ndensedA by said returning cooling mel In testimony whereof I have signed this specification.

ROBERT A. WEXNHARDT. 

